Irradiance
VOP node

Computes the irradiance (the global illumination) at the point P with
the normal N.

This operator computes the irradiance (the global illumination) at the
point P with the normal N.

The Bias parameter (bias) gives control over self-intersections. The
Samples value specifies the number of samples should be sent out to
filter rays. If the ray sent out to the scene misses everything, then it
is possible to specify an environment map to evaluate. Using the ray’s
direction, the environment map (envmap) specified will be evaluated and
the resulting color will be returned. Most likely, it will be necessary
to specify a transform space (envobj) for the environment map
evaluations. Also, if an environment map is specified, it is possible to
tint the resulting color (tint). If a ray misses all objects, you can
specify the background color (bgcolor) of the scene.

If the position (P) and normal vector (N) are not connected, the global
variables by the same names will be used instead. If the maximum ray
distance (maxdist) is not connected, the rays will be allowed to travel
to infinity.

Takes two values for alpha based on the surface orientation relative
to the camera and blends between the two with a
rolloff as the bias control, effectively removing the silhouettes of the
geometry edges.